• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 2
  • 1
  • 1
  • Tagged with
  • 5
  • 5
  • 2
  • 2
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Zavedení controllingu ve firmě Colas - CZ, a.s. / Implementation controlling in the firm Colas - CZ, Inc.

Jenča, Patrik January 2007 (has links)
My thesis deals with leading a machine of controlling to the company which enterprises in building and repairing roads and motorways. Concept of controlling isn´t still very used in the Czech Republic that´s why in the introdusing part I´m devotiny to definition and terms when it can work effectively. The second part of my thesis contains introdusing and evolutoin of the company, analysis of the present condition of conrtolling activities and deviding the costs of the firm. In the last part I´m analysing the lack of control to claiming costs and I´m proposing to lead a new position of controller, his taking part in the orgaization structure and then to create a new controlling department.
2

Active Vibration Control Of Smart Structures

Ulker, Fatma Demet 01 January 2003 (has links) (PDF)
The purpose of this thesis was to design controllers by using H1 and &sup1 / control strategies in order to suppress the free and forced vibrations of smart structures. The smart structures analyzed in this study were the smart beam and the smart &macr / n. They were aluminum passive structures with surface bonded PZT (Lead-Zirconate-Titanate) patches. The structures were considered in clamped-free con&macr / guration. The &macr / rst part of this study focused on the identi&macr / cation of nominal system models of the smart structures from the experimental data. For the experimentally identi&macr / ed models the robust controllers were designed by using H1 and &sup1 / -synthesis strategies. In the second part, the controller implementation was carried out for the suppression of free and forced vibrations of the smart structures. Within the framework of this study, a Smart Structures Laboratory was established in the Aerospace Engineering Department of METU. The controller implementations were carried out by considering two di&reg / erent experimental set-ups. In the &macr / rst set-up the controller designs were based on the strain measurements. In the second approach, the displacement measurements, which were acquired through laser displacement sensor, were considered in the controller design. The &macr / rst two &deg / exural modes of the smart beam were successfully controlled by using H1 method. The vibrations of the &macr / rst two &deg / exural and &macr / rst torsional modes of the smart &macr / n were suppressed through the &sup1 / -synthesis. Satisfactory attenuation levels were achieved for both strain measurement and displacement measurement applications.
3

Verification of Digital Controller Verifications

Wang, Xuan 10 November 2005 (has links) (PDF)
This thesis presents an analysis framework to verify the stablility property of a closed-loop control system with a software controller implementation. The usual approach to verifying stability for software uses experiments which are costly and can be dangerous. More recently, mathematical models of software have been proposed which can be used to reason about the correctness of controllers. However, these mathematical models ignore computational details that may be important in verification. We propose a method to determine the instability of a closed-loop system with a software controller implementation under l^2 inputs using simulation. This method avoids the cost of experimentation and the loss of precision inherent in mathematical modeling. The method uses the small gain theorem to compute a lower bound on the 2-induced norm of the uncertainty in the software implementation; if the lower bound is greater than 1/(2-induced norm of G), where G is the feedback system consisting of the mathematical model of the plant and the mathematical model of the controller, the closed-loop system is unsafe in a certain sense. The resulting method can not determine if the closed-loop system is stable, but can only suggest instability.
4

Digital Controller Implementation For Disturbance Rejection In The Optical Coupling Of A Mobile Experimental Laser Tracking Systems

Rhodes, Matthew 01 January 2006 (has links)
Laser tracking systems are an important aspect of the NASA space program, in particular for conducting research in relation to satellites and space port launch vehicles. Often, launches are conducted at remote sites which require all of the test equipment, including the laser tracking systems, to be portable. Portable systems are more susceptible to environmental disturbances which affect the overall tracking resolution, and consequently, the resolution of any other experimental data being collected at any given time. This research characterizes the optical coupling between two systems in a Mobile Experimental Laser Tracking system and evaluates several control solutions to minimize disturbances within this coupling. A simulation of the optical path was developed in an extensible manner such that different control systems could be easily implemented. For an initial test, several PID controllers were utilized in parallel in order to control mirrors in the optical coupling. Despite many limiting factors of the hardware, a simple proportional control performed to expectations. Although a system implementation was never field tested, the simulation results provide the necessary insight to develop the system further. Recommendations were made for future system modifications which would allow an even higher tracking resolution.
5

Automatic Translation of Moore Finite State Machines into Timed Discrete Event System Supervisors / Automatic Translation of Moore FSM into TDES Supervisors

Mahmood, Hina January 2023 (has links)
In the area of Discrete Event Systems (DES), formal verification techniques are important in examining a variety of system properties including controllability and nonblocking. Nonetheless, in reality, most software and hardware practitioners are not proficient in formal methods which holds them back from the formal representation and verification of their systems. Alternatively, it is a common observation that control engineers are typically familiar with Moore synchronous Finite State Machines (FSM) and use them to express their controllers’ behaviour. Taking this into consideration, we devise a generic and structured approach to automatically translate Moore synchronous FSM into timed DES (TDES) supervisors. In this thesis, we describe our FSM-TDES translation method, present a set of algorithms to realize the translation steps and rules, and demonstrate the application and correctness of our translation approach with the help of an example. In order to develop our automatic FSM-TDES translation approach, we exploit the structural similarity created by the sampled-data (SD) supervisory control theory between the two models. To build upon the SD framework, first we address a related issue of disabling the tick event in order to force an eligible prohibitable event in the SD framework. To do this, we introduce a new synchronization operator called the SD synchronous product (||SD), adapt the existing TDES and SD properties, and devise our ||SD setting. We formally verify the controllability and nonblocking properties of our ||SD setting by establishing logical equivalence between the existing SD setting and our ||SD setting. We present algorithms to implement our ||SD setting in the DES research tool, DESpot. The formulation of the ||SD operator provides twofold benefits. First, it simplifies the design logic of the TDES supervisors that are modelled in the SD framework. This results in improving the ease of manually designing SD controllable TDES supervisors, and reduced verification time of the closed-loop system. We demonstrate these benefits by applying our ||SD setting to an example system. Second, it bridges the gap between theoretical supervisors and physical controllers with respect to event forcing. This makes our FSM-TDES translation approach relatively uncomplicated. Our automatic FSM-TDES translation approach enables the designers to obtain a formal representation of their controllers without designing TDES supervisors by hand and without requiring formal methods expertise. Overall, this work should increase the adoption of the SD supervisory control theory in particular, and formal methods in general, in the industry by facilitating software and hardware practitioners in the formal representation and verification of their control systems. / Dissertation / Doctor of Philosophy (PhD)

Page generated in 0.1538 seconds